SHOULD I CHANGE CRANK ARM LENGTH?

Q: I have been riding 172.5mm crank arms for over two decades and never thought anything of it. Then, last week on a ride, the group was talking about how at my height (6-foot-1), I need to switch to 175mm. They had a lot of reasons, but they are all pretty set in their ways and still ride 23mm tires. Any insight you have would be much appreciated, because I’m not sure it’s worth the hassle and expense since two bikes have power meters.

A: This question comes at a unique time since we recently began our review of the new Canyon Grizl, which showed up with 170mm cranks instead of the more typical 172.5mm length for us. I’ve always said that it matters less than people make it out to be and really just slightly changes saddle height. Most of my road bikes are 172.5mm, all of my mountain bikes are 175mm, and my e-MTB is 165mm. 

So, in short, I wouldn’t change it unless you are having specific issues, and in most cases, a shorter crankarm would be better. During a pedal stroke on a shorter arm, your hip and knee don’t need to rotate as much. I have also noticed that riders with very aggressive positioning do better with shorter cranks because they have more room between the torso and knees when in the drops. Overall, I would see a professional fitter and have them assess your needs, but if you haven’t had issues in 20 years, just keep rocking what you have.